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 /*

 Copyright (c) 2007, Adobe Systems, Incorporated

 All rights reserved.

 Redistribution and use in source and binary forms, with or without

 modification, are permitted provided that the following conditions are

 met:

 * Redistributions of source code must retain the above copyright

   notice, this list of conditions and the following disclaimer.

 * Redistributions in binary form must reproduce the above copyright

   notice, this list of conditions and the following disclaimer in the

   documentation and/or other materials provided with the distribution.

 * Neither the name of Adobe Systems, Network Resonance nor the names of its

   contributors may be used to endorse or promote products derived from

   this software without specific prior written permission.

 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

 static char *RCSSTRING __UNUSED__="$Id: ice_socket.c,v 1.2 2008/04/28 17:59:01 ekr Exp $";

 #include <assert.h>

 #include <string.h>

 #include "nr_api.h"

 #include "ice_ctx.h"

 #include "stun.h"

 static void nr_ice_socket_readable_cb(NR_SOCKET s, int how, void *cb_arg)

   {

     int r;

     nr_ice_stun_ctx *sc1,*sc2;

     nr_ice_socket *sock=cb_arg;

     UCHAR buf[8192];

     char string[256];

     nr_transport_addr addr;

     int len;

     size_t len_s;

     int is_stun;

     int is_req;

     int is_ind;

     int processed_indication=0;

     nr_socket *stun_srv_sock=sock->sock;

     r_log(LOG_ICE,LOG_DEBUG,"ICE(%s): Socket ready to read",sock->ctx->label);

     /* Re-arm first! */

     NR_ASYNC_WAIT(s,how,nr_ice_socket_readable_cb,cb_arg);

     if(r=nr_socket_recvfrom(sock->sock,buf,sizeof(buf),&len_s,0,&addr)){

       if (r != R_WOULDBLOCK && (sock->type != NR_ICE_SOCKET_TYPE_DGRAM)) {

         /* Report this error upward. Bug 946423 */

         r_log(LOG_ICE,LOG_ERR,"ICE(%s): Error on reliable socket. Abandoning.",sock->ctx->label);

         NR_ASYNC_CANCEL(s, NR_ASYNC_WAIT_READ);

       }

       return;

     }

     /* Deal with the fact that sizeof(int) and sizeof(size_t) may not

        be the same */

     if (len_s > (size_t)INT_MAX)

       return;

     len = (int)len_s;

 #ifdef USE_TURN

   re_process:

 #endif /* USE_TURN */

     r_log(LOG_ICE,LOG_DEBUG,"ICE(%s): Read %d bytes %sfrom %s",sock->ctx->label,len,(processed_indication ? "relayed " : ""),addr.as_string);

     /* First question: is this STUN or not? */

     is_stun=nr_is_stun_message(buf,len);

     if(is_stun){

       is_req=nr_is_stun_request_message(buf,len);

       is_ind=is_req?0:nr_is_stun_indication_message(buf,len);

       snprintf(string, sizeof(string)-1, "ICE(%s): Message is STUN (%s)",sock->ctx->label,

                is_req ? "request" : (is_ind ? "indication" : "other"));

       r_dump(NR_LOG_STUN, LOG_DEBUG, string, (char*)buf, len);

       /* We need to offer it to all of our stun contexts

          to see who bites */

       sc1=TAILQ_FIRST(&sock->stun_ctxs);

       while(sc1){

         sc2=TAILQ_NEXT(sc1,entry);

         r=-1;

         switch(sc1->type){

           /* This has been deleted, prune... */

           case NR_ICE_STUN_NONE:

             TAILQ_REMOVE(&sock->stun_ctxs,sc1,entry);

             RFREE(sc1);

             break;

           case NR_ICE_STUN_CLIENT:

             if(!(is_req||is_ind)){

                 r=nr_stun_client_process_response(sc1->u.client,buf,len,&addr);

             }

             break;

           case NR_ICE_STUN_SERVER:

             if(is_req){

               r=nr_stun_server_process_request(sc1->u.server,stun_srv_sock,(char *)buf,len,&addr,NR_STUN_AUTH_RULE_SHORT_TERM);

             }

             break;

 #ifdef USE_TURN

           case NR_ICE_TURN_CLIENT:

             /* data indications are ok, so don't ignore those */

             /* Check that this is from the right TURN server address. Else

                skip */

             if (nr_transport_addr_cmp(

                     &sc1->u.turn_client.turn_client->turn_server_addr,

                     &addr, NR_TRANSPORT_ADDR_CMP_MODE_ALL))

               break;

             if(!is_req){

               if(!is_ind)

                 r=nr_turn_client_process_response(sc1->u.turn_client.turn_client,buf,len,&addr);

               else{

                 nr_transport_addr n_addr;

                 size_t n_len;

                 if (processed_indication) {

                   /* Don't allow recursively wrapped indications */

                   r_log(LOG_ICE, LOG_WARNING,

                         "ICE(%s): discarding recursively wrapped indication",

                         sock->ctx->label);

                   break;

                 }

                 /* This is a bit of a hack. If it's a data indication, strip

                    off the TURN framing and re-enter. This works because

                    all STUN processing is on the same physical socket.

                    We don't care about other kinds of indication */

                 r=nr_turn_client_parse_data_indication(

                     sc1->u.turn_client.turn_client, &addr,

                     buf, len, buf, &n_len, len, &n_addr);

                 if(!r){

                   r_log(LOG_ICE,LOG_DEBUG,"Unwrapped a data indication.");

                   len=n_len;

                   nr_transport_addr_copy(&addr,&n_addr);

                   stun_srv_sock=sc1->u.turn_client.turn_sock;

                   processed_indication=1;

                   goto re_process;

                 }

               }

             }

             break;

 #endif /* USE_TURN */

           default:

             assert(0); /* Can't happen */

             return;

         }

         if(!r) {

           break;

         }

         sc1=sc2;

       }

       if(!sc1){

         if (nr_ice_ctx_is_known_id(sock->ctx,((nr_stun_message_header*)buf)->id.octet))

             r_log(LOG_ICE,LOG_DEBUG,"ICE(%s): Message is a retransmit",sock->ctx->label);

         else

             r_log(LOG_ICE,LOG_NOTICE,"ICE(%s): Message does not correspond to any registered stun ctx",sock->ctx->label);

       }

     }

     else{

       r_log(LOG_ICE,LOG_DEBUG,"ICE(%s): Message is not STUN",sock->ctx->label);

       nr_ice_ctx_deliver_packet(sock->ctx, sock->component, &addr, buf, len);

     }

     return;

   }

 int nr_ice_socket_create(nr_ice_ctx *ctx,nr_ice_component *comp, nr_socket *nsock, nr_ice_socket **sockp)

   {

     nr_ice_socket *sock=0;

     NR_SOCKET fd;

     nr_transport_addr addr;

     int r,_status;

     if(!(sock=RCALLOC(sizeof(nr_ice_socket))))

       ABORT(R_NO_MEMORY);

     sock->sock=nsock;

     sock->ctx=ctx;

     sock->component=comp;

     if(r=nr_socket_getaddr(nsock, &addr))

       ABORT(r);

     if (addr.protocol == IPPROTO_UDP) {

       sock->type = NR_ICE_SOCKET_TYPE_DGRAM;

     }

     else {

       assert(addr.protocol == IPPROTO_TCP);

       sock->type = NR_ICE_SOCKET_TYPE_STREAM;

     }

     TAILQ_INIT(&sock->candidates);

     TAILQ_INIT(&sock->stun_ctxs);

     if(r=nr_socket_getfd(nsock,&fd))

       ABORT(r);

     NR_ASYNC_WAIT(fd,NR_ASYNC_WAIT_READ,nr_ice_socket_readable_cb,sock);

     *sockp=sock;

     _status=0;

   abort:

     if(_status) RFREE(sock);

     return(_status);

   }

 int nr_ice_socket_destroy(nr_ice_socket **isockp)

   {

     nr_ice_stun_ctx *s1,*s2;

     nr_ice_socket *isock;

     if(!isockp || !*isockp)

       return(0);

     isock=*isockp;

     *isockp=0;

     /* Close the socket */

     nr_ice_socket_close(isock);

     /* The STUN server */

     nr_stun_server_ctx_destroy(&isock->stun_server);

     /* Now clean up the STUN ctxs */

     TAILQ_FOREACH_SAFE(s1, &isock->stun_ctxs, entry, s2){

       TAILQ_REMOVE(&isock->stun_ctxs, s1, entry);

       RFREE(s1);

     }

     RFREE(isock);

     return(0);

   }

 int nr_ice_socket_close(nr_ice_socket *isock)

   {

 #ifdef NR_SOCKET_IS_VOID_PTR

     NR_SOCKET fd=NULL;

     NR_SOCKET no_socket = NULL;

 #else

     NR_SOCKET fd=-1;

     NR_SOCKET no_socket = -1;

 #endif

     if (!isock||!isock->sock)

       return(0);

     nr_socket_getfd(isock->sock,&fd);

     assert(isock->sock!=0);

     if(fd != no_socket){

       NR_ASYNC_CANCEL(fd,NR_ASYNC_WAIT_READ);

       NR_ASYNC_CANCEL(fd,NR_ASYNC_WAIT_WRITE);

       nr_socket_destroy(&isock->sock);

     }

     return(0);

   }

 int nr_ice_socket_register_stun_client(nr_ice_socket *sock, nr_stun_client_ctx *srv,void **handle)

   {

     nr_ice_stun_ctx *sc=0;

     int _status;

     if(!(sc=RCALLOC(sizeof(nr_ice_stun_ctx))))

       ABORT(R_NO_MEMORY);

     sc->type=NR_ICE_STUN_CLIENT;

     sc->u.client=srv;

     TAILQ_INSERT_TAIL(&sock->stun_ctxs,sc,entry);

     *handle=sc;

     _status=0;

   abort:

     return(_status);

   }

 int nr_ice_socket_register_stun_server(nr_ice_socket *sock, nr_stun_server_ctx *srv,void **handle)

   {

     nr_ice_stun_ctx *sc=0;

     int _status;

     if(!(sc=RCALLOC(sizeof(nr_ice_stun_ctx))))

       ABORT(R_NO_MEMORY);

     sc->type=NR_ICE_STUN_SERVER;

     sc->u.server=srv;

     TAILQ_INSERT_TAIL(&sock->stun_ctxs,sc,entry);

     *handle=sc;

     _status=0;

   abort:

     return(_status);

   }

 int nr_ice_socket_register_turn_client(nr_ice_socket *sock, nr_turn_client_ctx *srv,

                                        nr_socket *turn_socket, void **handle)

   {

     nr_ice_stun_ctx *sc=0;

     int _status;

     if(!(sc=RCALLOC(sizeof(nr_ice_stun_ctx))))

       ABORT(R_NO_MEMORY);

     sc->type=NR_ICE_TURN_CLIENT;

     sc->u.turn_client.turn_client=srv;

     sc->u.turn_client.turn_sock=turn_socket;

     TAILQ_INSERT_TAIL(&sock->stun_ctxs,sc,entry);

     *handle=sc;

     _status=0;

   abort:

     return(_status);

   }

 /* Just mark it deregistered. Don't delete it now because it's not safe

    in the CB, which is where this is likely to be called */

 int nr_ice_socket_deregister(nr_ice_socket *sock, void *handle)

   {

     nr_ice_stun_ctx *sc=handle;

     if(!sc)

       return(0);

     sc->type=NR_ICE_STUN_NONE;

     return(0);

   }